The present invention relates to a new and improved construction of a bimetallic thermo-release, especially for protective motor switches, which is of the type having at least one bimetallic release element operatively connected with connection means or connections for connecting electrical lines or conductors, a bimetallic compensation element for temperature compensation and a release or trigger element which can be activated as a function of the bending or deflection of the bimetallic release element and the bimetallic compensation element.
In a thermo-release or thermo-trigger of this type, as the same has been described for instance in Swiss Pat. No. 449,743, the bimetallic compensation element serves to eliminate the adverse effects of the ambient temperature upon the release or trigger point. With such heretofore known thermo-release devices it has been found to be disadvantageous that there is only compensated the effect of the ambient temperature upon the release or trigger point and there are not in any way taken into account heat sources which likewise effect the release point.